How fun is this? You can create audio posts for your Tumblr blog using nothing other than your phone (and your voice, of course). Write out what you're going to say, sing, play on the bongos -- whatever you have in mind. Then, call 1-866-584-6757 and leave your message. Your Tumblr followers will hear you -- yes, hear you -- in just seconds. Even in this technological day and age, that's pretty darn cool. Before you reach for your phone, though, you first need to go to the Tips section on Tumblr. From the Dashboard, look at the bottom-right of the page and click on About, and then on Tips in the right-hand box. Scroll down the Tips page until you see Phone in an Audio post, and the sentence that says Configure call in audio for your tumblelog. That opens up a box that guides you in configuring your phone for audio posts [source: Tumblr].